Steering methods and steering systems which work purely manually are known for industrial trucks. They have the disadvantage that different steering programs, for example, for operation of the industrial truck in longitudinal, transverse, or diagonal driving, cannot be implemented, or can only be implemented with significant mechanical effort.
In order to eliminate this disadvantage, so-called “steer-by-wire” steering systems have become known which bring about steering movements of the steerable wheels using steering motors. The steering motors are controlled in each instance by a steering computer as a function of the activation of the steering transducer and of the steering program selected.
DE 199 41 883 A1, for example, describes such a steering system where the steering activation of the steering transducer, for example, of the steering wheel, takes place without any feedback concerning the driving state of the industrial truck. Because steering is uniformly easy, independent of the driving state of the industrial truck, critical driving situations resulting from steering movements not appropriate to the speed can arise at higher speeds.
In order to increase driving safety, it is known, in “steer-by-wire” steering systems, to connect the steering transducer mechanically with a steering force simulator, which is supposed to generate steering and reset forces in the steering transducer as a function of the driving state, in each instance. However, in “steer-by-wire” steering systems configured in this manner, the effort and expenditure connected with the steering force simulator is disadvantageous, as is an increased technical susceptibility, and the problem that true-to-life simulation of the steering and reset forces is possible only with restrictions.